Each player starts with 501 points. The number of points collected while hitting a board with a dart is subtracted from the given player's points. The winner is the player who scores exactly 0 points that way.
It is a double out game, which means that players must hit a double that makes their score exactly zero to win the game.2. Bust
In case of a bust the player's score from the previous turn is restored. There is bust if one of the following events arise:
Players continue playing until one of them scores 0 points in total. The player who does so, wins the game.
If none of the players gets to zero in 20 turns, the player with the lower point wins.
If the scores are equal after 20 turns, the game will continue for another possible 10 turns.
During these extra turns, the player who gets to zero obviously wins. A player with lower score any time after the 20th turn also wins the match.
If the scores are equal after 20+10 turns, the match will end in a draw.